I. Field of Invention
The present invention relates to electrical apparatus protective interconnect modules. More specifically, the present invention relates to a novel disposable post-operative transcutaneous electrical nerve stimulator (TENS) protective interconnect module which provides battery power to and treatment signal output from a TENS unit while providing limited access to certain controls located on the TENS unit.
II. Background of the Art
Transcutaneous electrical nerve stimulator (TENS) units are used to generate electrical stimulation signals which are applied to the body of a patient to alleviate pain. Most recently, the use of a TENS unit has been viewed as a viable alternative for reducing pain a patient may experience in a post-operative environment. The use of a TENS unit in the post-operative environment has significant advantages in reducing pain as compared to narcotic drugs which have associated physiological side effects.
Previously, TENS units have included certain controls which the operator/patient may adjust. An example of such controls may be on/off, pulse amplitude, pulse width, pulse rate, and various forms of pulse modulation. It is difficult for someone less than a trained operator, skilled clinician, or repetitive user to properly adjust the controls to provide the most efficacious output signals. Therefore, in applications such as in the post-operative where typically a patient has had only limited exposure to TENS, it is desirable that the controls be preset to provide the preferred output signal for the particular application. Another consideration in the use of a TENS unit in the post-operative environment is the susceptibility of the controls to accidental adjustment or tampering by the patient. In a preferred mode, preset controls are desired which are inaccessable to the patient but which are accessable for adjustment by authorized and properly trained personnel.
Generally, TENS units have employed batteries typically four individual cells, a custom battery pack comprised of four cells or a 9 volt battery which are integrated within the TENS unit itself. Integration within the TENS unit itself may result in battery connections being affected by external contaminants. Contamination of battery contacts due to battery leakage, contact spring material oxidation, or too low of contact pressure on the battery springs due to use may result in intermittent or permanent device failure.
When using non-rechargeable disposable batteries, the hospital staff cannot easily distinguish new from partially discharged batteries and may inadvertently use partially discharged batteries on a new patient. With TENS units using multiple standard commercial cells, e.g. 4-AA cells, problems such as installation of batteries with incorrect polarization or theft of battery inventories may occur. With a conventional 9 volt battery, the installation factors are not a problem. However, limited power capacity restricts the usefullness of this type of battery. Also, due to the popularity of this type of battery, battery theft reduces the desirability of usage of this battery type.
When using rechargeable batteries, the hospital staff must either test or replace and recharge battery packs that are questionable prior to usage. Rechargeable battery packs would need to be recharged by hospital personnel prior to usage thereby requiring additional hospital staff time and facilities for this task. Efforts associated with both the monitoring of rechargeable battery status or the recharging of batteries can result in inefficient use of hospital personnel.
Other factors which affect the use of TENS unit in post-operative situation is that the TENS unit, battery pack and lead wires may be contaminated by liquid spills or other external contaminants. Even if no contamination were to occur by usage with a patient, typical hospital procedures would include cleaning of the device before use with another patient. Nevertheless, under any circumstances the unit and lead wires would have to be cleaned before usage with another patient. Again, a cleaning operation would require additional hospital staff resources.
Another disadvantage of a conventional TENS unit in the post-operative environment are the long term use related failures. Such failures appear, for example, in the TENS unit's lead wires which couple the TENS unit's electrical output signal to the electrodes. The leads may experience connector/lead stress fatigue or lead discontinuity due to conductor breakage, over long term use. In a re-use situation leads may need to be tested to ensure operability, thus requiring additional hospital staff resources.
It is therefore an object of the present invention to provide a new and improved electrical apparatus protective interconnect module which protects the electrical apparatus from external factors, such as contaminants and control tampering.
It is a further object of the present invention to provide a low cost, highly reliable, disposable TENS protective interconnect module, for use with a post-operative TENS unit, which provides reduced maintenance in the post-operative environment.
It is yet another object of the present invention to provide a TENS protective interconnect module wherein substantial portions of the protective interconnect module which come in contact with a patient are disposable.